Astronomy and Astrophysics Forum

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Join in expert discussion on the topics of Astronomy and astrophysics. This may include discussion on celestial objects, space, and the physical universe as a whole. Mainstream science only.
Undergrad Why are the centers of galaxies so bright?
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Undergrad Why don't we see the Geminids twice a year?
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Undergrad What will the gravitational field inside the Earth be?
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Undergrad Solar System's orbit around galaxy, a concise 3D description?
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Undergrad How Do We Measure Star Formation?
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Undergrad What math does one need to know prior to learning Astrophysics
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Undergrad Eye of the storm at Saturn's north pole
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Undergrad Why Hasn't the Moon Crashed into the Earth?
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Undergrad Could a Planet Thrive with Two Suns?
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Undergrad Is the Universe really infinite/absolute 0
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Undergrad Planets & Relativity: Time Dilation in Our Galaxy
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Undergrad Any difference on Satellite location between W135 and W075?
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Undergrad Calculations for sun position follower
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Undergrad White Dwarfs,Black Dwarfs & neutron star
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Undergrad What is different in Solar Radio vs Radio Flux 10.7 cm?
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Undergrad Is there some liquid planets out there?
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Undergrad Active Galaxies and the Unified Model
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Undergrad Low and high orbital energy differences (getting there and back)
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Undergrad Discovering the True Speed of Light: A Question on Its Absolute Nature
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Undergrad Is light pollution causing wasted energy and costing billions of dollars?
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Undergrad Is Space Considered a Medium for Photons and Other Waves?
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Undergrad Orphan planets, i.e., planets not in a solar system
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Undergrad Is a Webcam Better than a DSLR for Astrophotography?
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Undergrad Searching for Colliding Stars: Has the Phenomena Ever Been Observed?
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Undergrad Will Earth pass through the galactic plane in 2012?
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Undergrad Need Help Understanding Angular Resolution
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Undergrad Does Dark Energy Repel Light and Cause Damage?
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Undergrad Can Black Holes Bend Time?
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Undergrad How does momentum dumping work on the Hubble Space Telescope?
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Undergrad How to convert flux from counts to erg.
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Undergrad Urban Space Saving: Reducing Traffic with Raised Roadways and Shops
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Undergrad Can Amateur Telescopes Detect Exoplanets?
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Undergrad Just how dark is Pluto from orbit? How about Saturn?
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Undergrad Position and angle of Earth/Moon/Sun and timing
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Undergrad Could Ice Form Inside the Sun?
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Undergrad What is the Scientific Understanding of Gravity?
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Undergrad What Determines the Diameter of a Moon Halo?
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Undergrad Apparent size of comets in images from the SOHO satellite
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Undergrad Is Retro-Rocket Still a Relevant Term for Slowing Down Satellites?
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Undergrad Can someone explain abberation of starlight?
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Undergrad How Does the Moon Influence Earth's Rotation and Orbit?
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Undergrad Is Dark Rift a Rotating Cloud or a Dust Belt Surrounding the Galactic Center?
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Undergrad Backwards Orbiting Moon: Impact and Visibility with Earth's Rotation
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Undergrad Do You Know Why Stars Have Different Colors?
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Undergrad Q about moon and sun tides, energy related to comet strikes and the mass water?
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Undergrad How do you calculate declination and Right Ascension from Earth Coordinates?
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Undergrad Does Light Have Mass? Gravity Effects Explained
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Undergrad Can you have binary stars with the same radius but different masses?
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Undergrad Instruments and Imaging: How to prevent condensation inside a closed system?
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Undergrad Space: Is It an Idea or Physical Reality?
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Undergrad Can Slow Space Travel Overcome the Speed Barrier in Vacuum Flight?
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Undergrad Available Astronomy Research Topics?
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Undergrad Quick Question about the Doppler Effect
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Undergrad How Can I Estimate Local Sidereal Time in My Head?
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Undergrad Solar system space dust avg density[kg/m^3]
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Undergrad Question Gravity: Explaining Planetary Motion & Hailey's Comet
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Undergrad A basic question on gravity from a novice
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Undergrad What Would Happen If Mars Had a Higher Density and Maintained Its Radius?
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Undergrad Is the only evidence for an expanding universe the doppler Red Shift?
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Undergrad Which Observational Project sounds funner/easier?
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Undergrad The importance of atmospheres for the planetary temperature
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Undergrad Figuring Out Mysterious Meteorite: Speed, Trajectory & More
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Undergrad Perpendicular velocity of planets
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Undergrad Understanding Elliptical Orbits: Foci, Center, Barycenter, and Mass Relationship
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Undergrad Is the Sun Really Older Due to Relativity?
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Undergrad Could Dark Energy be Dark Matter cooling?
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Undergrad Stellar Nebulae and angular momentum
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Undergrad Can we give an analogy for nucleus to sun and electrons to planets
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Undergrad Horizontal + Celestial Coordinates to Geographic Coordinates
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Undergrad How to get longitude from Two Line Element (TLE)
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Undergrad .Understanding Stress on Space Elevator
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Undergrad What the minimum mass for a habitable exoplanet or moon?
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Undergrad A few questions about black holes
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Undergrad What would happen if someone was sucked into a black hole?
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Undergrad Where do the heaviest elements come from?
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Undergrad Do Black Holes Work Like a Sucked-Out Fire?
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Undergrad Can the merging of white dwarfs explain Type Ia supernovae explosions?
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Undergrad Relating Newton's universal law of gravitation with Kepler's 3rd law
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Undergrad Effect of Telescope Aperture Size on Spectrometer Resolution
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Undergrad What is the Correct Calculation for the Pressure at the Center of a Planet?
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Undergrad How does temperature change as you move away from the sun into space?
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Undergrad The Cause of Earth's Rotation: Faradey's Motor or Something Else?
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Undergrad Life on Mars: Did Asteroids Transfer Bacteria to Earth?
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Undergrad Atmospheric Density Profiles of Europa and Mars
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Undergrad Martian Core Composition: Is it Solid or Liquid? My Theory on Volcanic Activity
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Undergrad Escape velocity in the atmosphere
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Undergrad The Sun is very spherical - allegedly
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Undergrad Ultra-high-energy cosmic ray ≠ collision of 2 'normal' rays?
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Undergrad Which planet in this solar system would be most appropriate to terraform?
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Undergrad Orbital slingshot energy - energy from gravity?
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Undergrad Do Heavy Elements Come Only from Supernovae?
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Undergrad Expansion of space: Earth - Moon
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Undergrad Calculating Distances 1 Billion Light Years Away
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Undergrad What Would Happen if Our Moon Had a Moon?
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Undergrad How does declination and right ascension relate to latitude / longetude?
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Undergrad How do you relate space&time and matter&energy?
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Undergrad Minimum Distance Between Earth & Mars: Analytic Calc
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Undergrad Solar flares & CMEs: Serious threat?
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Undergrad Why Correct Horizontal Parallax Errors?
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Undergrad Can a Planet Support an Atmosphere with 50% Earth's Gravity?
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